1. Field of the Invention
The present invention relates to a door opening/closing device for controlling opening and closing of a door.
2. Description of the Related Art
Generally, a door opening/closing device for controlling opening and closing of a door of a vehicle is provided with a door driving mechanism that includes a door opening/closing motor that drives the door to be open or closed. The door opening/closing device also includes a latch for holding the door to be closed. The latch includes a closer mechanism having a closer motor that drives the latch so that the latch in a half-latch state is brought to a full-latch state, and a release mechanism including a solenoid that drives the latch so that the latch in the full-latch state is released. In other words, in the above door opening/closing device, the door-closing operation is succeeded from the door driving mechanism to the closer mechanism when the door has brought to the half-latch state. Moreover, a door-opening operation is succeeded from the release mechanism to the door driving mechanism when the door has brought to a position at which the latch is released.
In the door-closing operation, a reaction force of a weatherstrip occurs. Due to the reaction force, transition from the door driving mechanism to the closer mechanism may not be conducted properly. In a conventional technology, for example, such a region that the door driving mechanism and the closer mechanism are simultaneously driven after the latch has brought to the half-latch state. Accordingly, the door is securely moved to a position to be the half-latch state by the door driving mechanism against the reaction force so that the closer mechanism can succeed the door-closing operation to bring the latch to the full-latch state (for example, Japanese Patent No. 2715747).
Another conventional door opening/closing device that includes reels and cables for controlling opening and closing of the door. The door opening/closing device rotates the reels connected with respective ends of the cables fixed to the door in forward and reverse directions with a motor to cause the reels to wind the cables therearound. In this apparatus, each of the reels includes a large diameter portion that winds the cable so as to provide a relatively high speed and a low power operation of the door, and a small diameter portion that winds the cable so as to provide a relatively low speed and a high power operation. Thus, the door is first moved at a high speed in a door-closing direction, and then, with a high power so that the door is closed against the reaction force (for example, Japanese Patent No. 2554786).
However, in the conventional door opening/closing device disclosed in Japanese Patent No. 2715747, if a load occurs at the transition between the door driving mechanism and the closer mechanism while the door driving mechanism and the closer mechanism are simultaneously driven, a catching detector (arranged separately) can erroneously determine that something is caught in the door. In this case, the door is controlled to be reversely moved to the door opening direction. Therefore, a specific control must be conducted to perform the transition from the door driving mechanism to the closer mechanism.
In the conventional door opening and closing device disclosed in Japanese Patent No. 2554786, if the cable is stretched or shrunk, or if the cable slides on the reel, power can be provided at positions deviated from desired positions.